Earth boring machine



y 1950 L. J. APPLEGATE 2,509,410

EARTH BORING MACHINE Filed Aug. 29, 1946 2 Sheets-Sheet l INVENTOR-LESTER J APPL EGATE ATT? May 30, 1950 L. .1. APPLEGATE EARTH BORINGMACHINE 2 Sheets-Sheet 2 Filed Aug. 29, 1946 INVENTOFL LEETER J APPLEGATE ATT'Y Patented May 30, 1950 UNITED STATES PATENT OFFICE 3 Claims,

This invention relates generally to earth boring machines and inparticular to a ,post hole digging attachment for a tractor,

An object of this invention is to provide an im.- proved post holedigging machine.

A further object of this invention is to provide a post hole diggingmachine in which an auger is completely operable and adiustabl movableto a desired digging angle by the tractor operator while he is in aseated position on the machine.

Another object of this invention is to provide a post hole dig ingattachment :for a tractor in which the operation or th auger iscompletely visible from the ,operators seat on the tractor, and manuallymovable by the tractor operator while in a seatedposition from anupright digging position to a horizontal carrying position to one sideof the operators seat.

A still further object of this invention is to pro-. vide a tractor posthole digging attachment which is compact and light in weight, capable ofbeing assembled with and removed from the tractor by one man with aminimum of time and effort; adapted for easy and quick manipulation bythe tractor operator While he is on the tractor, and capable of digginga series of holes in a short period of time.

A feature of this invention is found in the provision of a post holedigging attachment for a tractor in which an auger is supportcdfor axialand rotational movement rearwardly of the tractor at a position to oneside of the tractor oper ators seat. The auger shaft is driven from apower take-off on the tractor and is axially moved by a hydrauliccylinder extended axially of and in a parallel relation with the augershaft, with the hydraulic cylinder being in fluid connecticn with apumpunit on the tractor. A valve means for controlling the application offluid under pressur to the cylinder, is located adjacent to the tractoroperators seat so that the auger is completely visible and operable bythe tractor operator while he is in aseated position.

Another feature of this inventionis found in the provision of a posthole digging attachment for a tractor in which a support means for anauger shaft is mounted on an upright frame, positioned rearwardly of thetractor operator's seat, for rotational movement about an axis extendedtransversely of the tractor. The auger is located to the inside. of. oneof the rear traction wheels and journaledon the support means forrotational and axial movement. A locking means on the upright frame,arranged to one side of the operators seatis adapted to releasably loclgthe auger shaft support means against rotation between rotated positionsproviding for an up-. right digging position of the auger shaft and acarrying or transport position in which the auger is extendedlongitudinally of the tractor across the tractor rear axle between theoperators seat and a rear traction wheel. Rotation ofthe auger shaftsupport means, on release ,of the locking means, is accomplishedmanually.

Still another feature, of this invention is found in the provision of apost hole digging attachment for a tractor "in which an auger, supportedrearwardly of the tractor to oneside of the opera ators seat, is axiallymovable by a hydraulic cylinder carried on the auger shaft supportingmeans. The fluid system for the cylinder in! cludes a pump and fluidreservoir unit on the tractor and a manually operated control valvelocated adjacent to the tractor operator's seat. In order to maintainthe supply :of the fluid to the cylinder at a pre-determined workingpres. sure the fluid system is provided with an autos matically operablevalve member which connects the cylinder fiuidsupplyline with the fluidreservoir when a pressure greater than such pro-de termined workingpressure is elfected in the cylinder supply line.

Further objects, features and advantages of this invention will becomeapparent from the following description when taken in connection withaccompanying drawings in which:

Fig. 1 is a side elevational view of a tractor showing the post holedigging attachment of this invention in assembly relation therewith,with parts of the tractor being removed and in sec-1 tion to moreclearly show such assembly;

Fig. 2 is a side elevation of a fragmentary por-v tion of the assemblyin Fig. 1 with parts shown in changed positions;

Fig. 3 isa fragmentary detail perspectiveview;

Fig. 4 is a rear elevational view of the assembly shown in Fig. 1;

Fig. 5 is an enlarged sectional detail view taken on the line 5-.-5 inFig. 4;

Fig. 6 is a perspective view of a lock lever;

Fig. '7 is an enlarged elevational View, with some parts broken away andin section, showing the assembly of the auger shaft with a hydrauliccylinder adapted to axially move the same;

Fig. 8 is a sectional detail view taken on the line 8--B in Fig. '7; and

Fig. 9 diagrammatically illustrates a iiuid SYS! term for auger shafthydraulic cylinder shown in Fig. 7.

With reference to the drawings, the post hole digging attachment of thisinvention is illustrated in Figs. 1 and 4 in assembly relation with atractor including a frame I5, front steering wheels l8, a rear axle I1for supporting rear traction wheels l8 and lim and a tractor operatorsseat l9, disposed substantially between the rear traction wheels. An oilpump 2 including a fluid reservoir, is formed as part of the tractor forthe purpose of supplying oil under pressure to attachments adapted foruse with the tractor. A tractor draw bar 22 is supported rearwardly ofthe tractor on transversely spaced rear uprights 23 which are clampedagainst the rear side of the axle |1 through front upright clamp bars 24and clamping bolts 26. The tractor thus far described is of a usualcommercial type, known as the Farmall.

The attachment of this invention includes a transverse upright frame,indicated generally as 25, and comprised of a pair of transverselyspaced upright frame members 21 and 21a of an angle iron construction,and pivotally supported at their lower ends on bolts 28, carried inupright lugs 29 secured to the draw bar 22 (Figs. 1, 3 and 4). The framemembers 21 and 21a are connected together by crossed brace bars 3|. Anadjustable pivoted movement of the upright frame 25, in a directionlongitudinally of the tractor, is maintained by a pair of longitudinallyextended adjustment rods 32, which are pivoted at their forward "ends onbolts 33 carried in the top ends of the front upright clamp bars 24. Therear ends of the adjustable rods 32 are connected in a bolt and slotconnection, as indicated at 34, with the upper ends of the frame members21 and 21a. 7

A housing unit, designated generally as 36, is comprised of a gearcasing member 31, and a tubular member 38 secured to one side of thegear casing through bolted flange members 39. The tubular member 38 isrotatably supported transversely of the tractor, at the upper end of theupright frame 25, by means including a split bearing member 4| (Figs. 4and mounted on the upright frame member 21 by a bolt 42, and a U-bearing43 secured to the upright frame member 21a, with the tubular member 38being of a, length such that its opposite ends are extended laterallyoutwardly from the sides of the upright frame 25. The gear casing 31,secured to one end of the tubular member 38, is arranged rearwardly ofthe tractor at a position between the rear axle wheel I80, and theoperator's seat I9, for a purpose which will appear later.

The tubular member 38 is locked against rotation on the upright frame 25by the provision of a locking means including an eye bolt 46 (Figs. 4and 5), having its shank loosely extended through the frame member 21and the split section 41 'of the bearing 4|, such that its eye 48 isprojected forwardly of the leg member 49 of the frame member 21. Alocking lever 5| (Figs. 5 and 6) has a U-shaped member 52 integrallyformed atone end and adapted to straddle the eye '48 of 'the bolt 46. Apin 53 is extended through the legs of the U-member 52 and through theeye '48 whereby to pivotally support the locking lever 5| on the pin 53.

The free ends 54 of the legs of the U-member 52 are of a rounded contourand adapted for riding engagement against the forward side of the leg 49of the frame member 21. Thus, on rotation of the lever 5|, to its dottedline position shown in Fig. 5, the bearing 4| is released from aclamping or frictional engagement with the tubular member 38 whereby thetubular member is freely rotatable within the bearings 4| and. 43. Onmovement of the locking lever 5| to its full line position, also shownin Fig. 5, the bearing 4| is clamped into frictional engagement with thetubular member 38 to lock such member against rotation on the frame 25.

An auger shaft 56 (Figs. 4 and 7) is extended through the gear casing 31in the plane of, but at right angles to the tubular member 38. Bearings51, in the casing 31, journal the auger shaft 56 for rotational andaxial movement. Mounted on the auger shaft 56, within the casing 31, isa bevel gear 58, which is in a key and slot connection 59 with the augershaft. A transverse shaft 6| (Fig. 4), rotatably supported in thetubular member 38, has one end projected within the gear casing 31 forcarrying a bevel gear 62, adapted for meshing engagement with the bevelgear 58. The opposite end of the transverse shaft 6| carries a pulley63, which is connected through a belt 64 with a belt or power take-off66 of the tractor. It is thus seen that the auger shaft 56 is operatedfrom the tractor belt pulley 66 through the shaft 6| and the gears 58and 62.

An axial movement of the auger shaft 56 is accomplished by meansincluding a hydraulic cylinder 61 (Fig. '1) supported in a spacedparallel relation with the auger shaft 56 by strap members 68, securedby welding or other suitable means, to opposite ends of a tubularextension or guide 69 secured on the casing 31 and adapted to receivethe upper portion of the auger shaft 56.

A piston 1|, for the cylinder 61, carries a bearing arm 12 at its freeend (Figs. 7 and 8). The auger shaft 56 is. rotatably extended through abearing member 13 mounted at the free end of the bearing arm 12 whichmember 13 is arranged between a pair of axiall spaced collars 14 and 15,mounted on the auger shaft 56. The cylinder 61 is of a double actingtype and on the admission of fluid therein to move the piston 1|downwardly, as viewed in Fig. '7, the bearing arm 12 engages the collarmember 15 whereby the auger shaft 56 is moved downwardly in response toa downward movement of the piston 1|. On an upward movement of thepiston 1|, the bearing arm 12 engages the collar member 14 to in turnprovide for an upward movement of the auger shaft 56. It is seen,therefore, that the auger shaft 56 is moved upwardly and downwardly indirect response to an upward and downward movement of the piston 1|.

The fluid system for the cylinder 61 (Fig. 9) includes the pump 2| anda, fluid reservoir 16, generally formed as part of the pump 2|, and atwo-way valve unit, indicated generally as 11. The valve unit 11includes four connections 18, 19, and 8|. The pump outlet 82 isconnected with the valve connection 18 by a conduit 83, while the valveconnections 19, 80 and 8| are connected respectively with the top 84 ofthe cylinder 61, the reservoir 16, and with the bottom 86 of thecylinder 61 through conduits 81, 88 and 89. A valve member is providedwith an actuation lever 9| and oppositely arranged fluid passages 10 and19a.

In order to raise the piston 1|, and in turn the auger shaft 56, theactuating lever 9| for the valve unit 11, is moved to its full lineposition, shown in Fig. 9, whereby fluid under pressure from the pump 2|passes through the conduit 83, fluid passage 10a, and through theconduit 89 to the lower end 86 of the cylinder 61.

011 from the upper end of the cylinder .61! is returned to the reservoir16 through conduitvflfl, fluid passage .10 and conduit 88. When :theauger shaft '55 is 'to "be lowered, the lever 91 is moved to its dottedline position A, also illustrated in Fig. 9, whereby oil under pressurefrom the pump 39 is supplied to upper end 84 of the cylinder 61 throughthe conduit 8-3, fluid passage 10, and conduit 81. Concurrently oil isdischarged from thecylinder, through the conduit 89, oil passage a andconduit 88 to the reservoir F5. Fhe valve member 85 interrupts the flowof oil bement of thevalve lever 9| to its dotted line positionillustratedat B, whereby theoil passages!!! and 10a are in positions outof communication with the valve connections Iii--81.

In the operation of the post hole digging attachment of this invention,the upright frame is initially pivotally adjusted to provide for adesired tension in the driving belt 64 connected between the tractorpulley 66 and the driven pulley 63 on the transverse shaft 51. With thelocking lever '51 in its position for releasing the tubular member 38,the tubular guide 59 and the cylinder 61 are manually gripped andmanipulated to move the auger shaft 56 to a substantially upright orperpendicular position. Thus if the holes are to be drilled into a.substantially fiat or horizontal ground surface the auger shaft 56 willbe moved to its position shown in Fig. 1. Where the holes are to bedrilled in an inclined or oped ground surface, so that the tractorwheels 16 and I8 and 18a are supported at .different ground elevations,the auger shaft 55 would be inclined to one side or the other of itsposition illustrated in Fig. l, to accommodate the inclination of theground surface. On movement of the auger shaft to a substantiallyperpendicular position, regardless of the slope of the ground surface,the locking lever 5| is operated to lock the tubular member 38 againstrotation within the bearings M and 43.

With the auger shaft 56 in its digging position, the control lever 9| ofthe valve unit 11 is actuated to initially provide for a downwardmovement of the auger shaft. When the hole has been dug to a desireddepth the valve lever BI is again operated to actuate the piston H toraise the auger shaft. As appears in Fig. 1, the valve control lever 9|is located adjacent to the tractor operators seat [9 so as to be readilymanipulated by the operator while he is in a seated position. Also, byvirtue of the auger shaft 55 being arranged rearwardly of the tractorand in a position to one side of the operator's seat is (Figs. 1 and 4),the entire digging operation is completely visible to the tractoroperator while in a seated position by his merely turning a little toone side and looking in a rearward and downward direction. Further, thelocking lever 5|, and the cylinder 61 and guide member 69, are allwithin easy reach of the tractor operator while he is in a seatedposition, so that adjustment of the auger haft to a proper uprightdigging position can also be accomplished by the operator withoutrequiring his dismounting from the tractor.

In some instances rocks or other hard materials are encountered by theauger during a digging operation. To prevent any damage to the auger orto the attachment when this condition occurs, the fluid system for thecylinder 61 is provided with a check valve 92 (Fig. 9) contor.

nected in .a :by pass lineren between-the conduits 8.! and 189. Thevalve szqincludes .a ball valve member .53 amovable 'toan .open positionagainst a coil spring 94 in response to the fluid pressure within theconduit @831, to automatically by pass oil from the conduit :81 to theconduit 89, when the pressure of the oil .in the :conduit .8] exceeds apredeterminedworking pressure :as determined by the pressure ofthespringil i acting tomaintain the ball valve :93 in a valve closingposition.

Thus .on thestriking .of a rock, .or the like, by the auger, thepressure of the fluid supplied to the cylinder J61 through the conduit81'! will increase only to the cylinder-working "pressure as determinedby. :the pressure of the spring 94. When this pressure is exceeded andthe valve 193 is opened, oil from the conduit 81 is by passed throughthe linei=into the conduit 89 andthence through the fluid passage 10aand conduit 88 back to the reservoir 16..

In transporting .or carrying the digging attachment. over "the highwayor over a field to its place of work, the auger shaft 56, on release ofthe locking lever 5rl, is movable to a substan-,

tiallyhorizontalposition, illustrated in Fi 2, and extendedlongitudinally of the tractor between the .operators seat 1.9 and therear traction Wheel Ina. The auger shaft 56 is thus. extended across thetop. of the rear axle I] so as to be completely free of anyobstructionsonthe ground, and is entirely .below the line of vision of the tractoroperator so as not to impair his visibility in any "way for steering andoperating the trac- Further, with the auger shaft in its raised orretracted position for transporting purposes, only the lower portionthereof is extended rearwardly from the tractor so that it offers only aminimum of interference with the usual turning space required for :thetractor. It is apparent of eourse,:that the augerashaft 5.6-,ispositively maintained in its transport position on movement of the lever5| to its locking position.

From a consideration of the above description, it is seen that theinvention provides a post hole digging attachment for a tractor which isof a simple and compact construction, and comprised of a relatively fewnumber of parts capable of being assembled on and removed from a tractorby one man in a relatively short period of time. Further, a diggingoperation is capable of being completely performed by the tractoroperator while he is in a seated position since all of the controls forthe entire digging operation are readily accessible and within an easyarms reach from the operators seat.

It is also to be noted that the rod Ha of the piston H is of a largediameter relative to the diameter of the cylinder 6'1, being on theorder of 1 for the piston rod and 2" for the cylinder. As a result theupward travel of the auger shaft 56 takes place at a faster rate thanits downward travel so as to shorten the time period required for acomplete digging cycle.

Although the invention has been described with respect to a preferredembodiment thereof, it is to be understood that it is not to be solimited since changes and modifications can be made therein which arewithin the full intended scope of this invention, as defined by theappended claims.

I claim: l

l. A post hole digging machine including a portable frame, an uprightframe supported adj acent one end of said frame, a transverse shaft onsaid upright frame, first means for rotatably supshaft, a housing forsaid auger shaft supported on said first means, means in said housingfor 5, connecting said two shafts, journal means in said M housingsupporting said auger shaft for rotational and axial movement, means foraxially moving said auger shaft including a hydraulic cylinder mountedon said housing, a piston for said cylinder, means connecting said augershaft with the free end of said piston, and means on said portable framefor rotating said transverse shaft and for supplying fluid underpressure to said cylv ing unit in a parallel relation with said guide 2.A post hole digging attachment for a tractor inder.

having a rear axle with traction wheels thereon,

a tractor operators seat, and a transverse draw I bar positionedrearwardly of said axle compris- 1.5;

ing, an upright frame mounted'on said draw bar, a transverse tubularmember on said upright frame at a position above the level of said axle,

means rotatably supporting said tubular member on said upright frame,means for releasably locking said tubular member against rotation, ashaft rotatably extended through said tubular member, tractor operatedmeans for driving said shaft, a housing member supported on one end ofsaid tubular member to the inside of one of said traction wheels, anauger shaft supported in said housing for rotational and axial movement,means on said housing operable from said tractor for axially moving saidauger shaft, and means within said housing for connecting said twoshafts, with said housing and tubular members, on release of saidlocking means, being rotatable as a unit to provide for a movement ofsaid auger shaft between an upright digging position and a substantiallyhorizontal carrying position ex-' tended longitudinally of said tractorbetween said seat and traction wheel. 3. A post hole digging attachmentfor a tractor comprising a transversely extended housing unit rotatablysupported at one end of said tractor, means for releasably locking saidhousing unit against rotation, a transverse shaft rotatably supportedwithin said housing unit and adapted to be driven from a power take oilon the tractor, an auger shaft supported at one end of said housing unitfor rotational and axial movement, upright guide means on said housingunit for guidably supporting said auger shaft, means connecting said twoshafts, means for axially moving said auger shaft including an uprighthydraulic cylinder mounted at said one end of the hous means, a pistonfor said cylinder movable from the lower end thereof, means fixed at thelower J end of said piston and connected with said auger 'shaft toprovide for an axial movement of the auger shaft in response to amovement of said :1 piston, and tractor operated means for supplyingfluid under pressure to said cylinder.

LESTER J. APPLEGATE.

REFERENCES CITED v The following references are of record in the 3'0file of this patent:

UNITED STATES PATENTS

